Research into nitrogen use efficiency in wheat has revealed how modern breeding can optimise yield, nitrogen uptake and water-use efficiency and enable climate-smart, sustainable agriculture.

The University of Western Australia Institute of Agriculture Director Hackett Professor Kadambot Siddique co-authored three research papers on nitrogen efficiency in wheat, in collaboration with Northwest A&F University and Shanxi Agricultural University in China, and the International Maize and Wheat Improvement Center. 

While improving wheat yield and nitrogen use efficiency, contemporary breeding programs inadvertently reduce the adaptability of new cultivars to less favourable environments.  Excessive application of fertilisers raises production costs, increases greenhouse gas emission and poses a threat to agricultural sustainability.

A study published in European Journal of Agronomy found modern wheat achieves higher yields under high nitrogen inputs, but gains under medium and low nitrogen applications remain limited.  

“By effectively coordinating nitrogen distribution across vegetative tissues, we can improve nitrogen use efficiency and increase grain protein content in wheat.”

Research published in Field Crops Research, complemented this study by showing modern breeding has strengthened wheat root systems, boosting nitrogen absorption and translocation. 

The improvements allowed wheat to recover more fertiliser nitrogen and leave less residual soil nitrogen, promoting efficient and sustainable farming practices.

A study, published in Plant and Soil, examined how wheat breeding and nitrogen management shaped root system architecture and water-use efficiency. 

Researchers found modern wheat cultivars have progressively improved grain water-use efficiency. Under reduced nitrogen, deeper roots enhance access to subsoil moisture, while under adequate nitrogen, roots grow mainly in the topsoil.

“Future wheat breeding programs should prioritise root system optimisation to enhance fertiliser nitrogen uptake and minimise residual soil nitrogen,” Professor Siddique said.

“By coordinating breeding with nutrient and water management, we can develop wheat varieties that thrive even in challenging, dryland environments, ensuring sustainable and productive farming for the future.”